1. Field of the Invention
The present invention relates to rack-mountable equipment with a heat-dissipation module and data interconnects, and also relates to a receptacle that receives an optical transceiver and that has increased cooling.
2. Description of the Related Art
Electronics racks are standard components for mounting a wide variety of electronic components and equipment in data, computing, and/or communication systems. Data centers typically have large numbers of racks, each filled with various pieces of electronic equipment, such as servers. A standard electrical rack has a 19″ width, which can support assemblies that mount into the rack with a width of 17.25″. Multiple assemblies can be mounted in each rack, one above the other. These assemblies typically are supported by a front bezel formed from cut outs in a flat piece of sheet metal that has clearance holes or slots along its edges to secure the bezel to the rack.
The rack-mountable electronic components often generate heat that needs to be removed from the rack to avoid overheating of the various electronic components. Typically cooling is provided by a fan that forces air across a heat sink that is in thermal contact with the temperature-sensitive, heat-producing electronic components.
The rapid increase in data storage and high-bandwidth communication driven by Internet expansion is increasing the need for dense interconnection systems in data centers. These data centers are typically composed of rows of racks of servers. These servers need to be in high-bandwidth communication with other servers in the data centers. The high-bandwidth communication can be supported by either shielded electrical cables or increasingly active optical cables. Active optical cables support longer transmission distances and higher transmission bandwidths. An active optical cable typically has an optical engine incorporated into a transceiver on at least one end of the cable that transforms electrical signals into optical signals (transmission (Tx) function) and transforms optical signals into electrical signals (receiver (Rx) function). An electronics rack can have hundreds or even thousands of interconnections, each of which generates heat that must be removed from the electronics rack. The inability to remove this heat can result in accelerated aging and/or premature failure of the interconnection or other components in the electronics rack. There is a need to provide a rack mounting system that facilitates high-heat removal and dense packaging of the interconnections.
FIG. 21 shows a known active optical cable 200 including a cable 201 and a transceiver 203. The transceiver 201 shown in FIG. 21 is compatible with SFF-8436 QSFP+ multi-source agreement revision 4.8, Oct. 31, 2013, hereby incorporated by reference in its entirety. Other known types of transceivers include SFP, QSFP, microQSFP, etc. The transceiver 203 can mate and unmate with receptacles in a rack (the receptacles and the rack are not shown in FIG. 21). The receptacles can be mounted to a printed circuit board (PCB). Mating the transceiver 203 to the receptacle creates mechanical and electrical connections. Electrical signals can be transported between the receptacle and the PCB. The transceiver 203 includes a pull tab 202 and an edge card 204. The pull tab 202 is optional and can be used to unmate the transceiver 203. The edge card 204 can mate with a connector within the receptacle. The edge card 204 can transport electrical signals to/from the transceiver 203.
The transceiver 203 can be optical, electrical, or hybrid of optical and electrical. If the transceiver 203 is optical, then the cable 201 includes optical fibers that transport, in which transport means receive and/or transmit, optical signals. The optical fibers can be single-mode or multimode fibers. The transceiver 201 can include an optical engine for transforming optical signals to electrical signals and/or electrical signals into optical signals.
If the transceiver 203 is electrical, then the cable 201 includes electrically conductive wires that transport electrical signals. The cable 201 can be, for example, coaxial cable, which is sometimes referred to as coax and which includes a single conductor surrounded by a dielectric and a shield layer, and twinaxial cable, which is sometimes referred to as twinax and which includes two conductors surrounded by a dielectric and shield layer. The cable 201 can also include other suitable transmission lines. The transceiver 201 can include contain electronic circuitry that transport electrical signals, including, for example, high-bandwidth electrical signals.
If the transceiver is a hybrid, then the cable 201 includes both optical and electrical cables. The transceiver 203 includes both an optical engine that transforms optical signals into electrical signals and/or electrical signals into optical signals and electronic circuitry that are appropriate for transmitting and/or receiving electrical signals from the electrical cable.
There is an increasing need for smaller transceivers that can be more tightly packed together and higher bandwidth transceivers. However, as channel density and bandwidth increased, the heat generated by the transceiver increases, which can cause excessive temperatures in the transceiver. Excessive temperatures can lead to premature failure and poor performance. Thus, there is a need for a transceiver receptacle that provides improved cooling for densely packaged, high-bandwidth transceivers.
FIGS. 22-24 show a known receptacle 205 that can be used with an electronics rack. The receptacle 205 can be mounted to a rack mount, which can then be mounted to an electronics rack. The receptacle 205 includes a cage 216 with mounting pins 217 and receptacle connectors 220 within the cage connected to wafers 222. Each wafer 222 is a module that includes a molded insert and a lead frame. The lead frame includes electrical contacts that each provide an electrical path for transmitting electrical signals. The molded insert is molded around the lead frame so that the electrical contacts are fixed with respect to each other within the wafer 222. The wafers 222 can be inserted into the receptacle connector 220 such that the wafers 222 are arranged side-by-side to each other so that the electrical contacts of adjacent wafers 222 are fixed with respect to each other in the receptacle connector 220. The cage 216 includes electromagnetic shields 218, faceplate 219, and slots 211. Transceivers can be inserted into the slots 211 to engage with the receptacle connectors 220. The receptacle connectors 220 are connected to wafers 222 that block or impede air flow.
During operation, the electronic components of the transceivers generate heat, which is mostly dissipated through the upper and lower walls, with a small amount being dissipated through the side walls. The heat dissipated into the passage 207 cannot be adequately removed because the wafers 222 block the flow of air in a direction from faceplate 219 to receptacle connector 220. As shown in FIG. 23, it is known to use holes in the sides of the cage 216. The location and size of the holes restrict the amount of air that is available to move through the cage 216 for cooling, particularly when a transceiver is inserted into the cage 216. But these side holes do not effectively remove the heat within the passage 207 (FIG. 22) and thus do not effectively remove heat from the transceivers. For interior transceivers in arrays 3×2 and bigger, the holes in the sides are not effective or adequate because the heat has to flow from an interior passage to an exterior passage with the sides holes. If the heat in the passage 207 cannot be adequately removed, the transceivers can undergo accelerated aging and/or prematurely fail. Thus, there is need for a receptacle with improved heat management.